1. Field of the Invention
The present invention relates to a refrigerated centrifuge and, in particular, to a refrigerated centrifuge in which the bowl is removable therefrom.
2. Description of the Prior Art
Some centrifuge instruments are capable of refrigerating the bowl in which the rotating member, or rotor, is received. This is done to more effectively control the temperature of the samples for material under test. Exemplary of such refrigerated centrifuge instruments are those sold by E. I. du Pont de Nemours and Company, Inc., as "RC-3B," "RC-5C" and "OTD." These instruments respectively operate in the low speed, superspeed and ultraspeed ranges. In each case refrigeration for the bowl is provided by a refrigeration coil which is closely wrapped about the exterior of the bowl or, in some cases, formed integrally therewith. U.S. Pat. No. 3,409,212 (Durland et al.) discloses a refrigerated bowl of the type having refrigerant coils surrounding the chamber.
Other centrifuge instruments, such as that disclosed in U.S. Pat. No. 4,512,758 (Wedemeyer et al.), may be refrigerated through the use of a thermoelectric temperature control assembly which includes an array of thermoelectric heating and cooling elements mounted within the housing of the centrifuge and disposed beneath the bowl.
A refrigeration system which uses the circulation of a refrigerant such as freon through the refrigeration coil provides both heating and cooling effects that are believed to be more efficient by at least an order of magnitude over a temperature control system that uses thermoelectric cooling devices. However, since the coils are at least physically close if not integrally mounted with the bowl and also interconnected with the refrigeration system it is difficult and a time-consuming process to remove the bowl assembly. Thus, in those instances when it is believed necessary or desirable to quickly and efficiently remove the bowl assembly the interconnection of the refrigeration coil into the refrigeration system makes this difficult.
In view of the foregoing it is believed advantageous to provide a centrifuge instrument in which the bowl is refrigerated using the more efficient circulating refrigerant system yet, at the same time, in which the bowl may be quickly and expeditiously removed from the interior of the casing.